1. Field of the Invention
The present invention relates to a refill case for accommodating staple-sheets formed by connecting straight staple members, and to a staple cartridge into which the refill case is attached so as to supply staples to an electric stapler.
2. Related Art
A paper handling device used as a paper finisher provided at a back stage of an image forming apparatus such as a copying machine or a printer includes an electric stapler for stapling plural paper sheets in a set (refer to Patent Document 1). The electric stapler is so constituted as to be capable of attaching and detaching a staple cartridge. The staple cartridge is so constituted as to be capable of attaching and detaching a refill case in which staple-sheets, each of which is formed by connecting straight staple members in a sheet shape, are stacked and accommodated. Further, the electric stapler is frequently arranged so that a staple is driven out from a downside and penetrates the paper sheets and legs of the penetrating staple are bent from an upside. Further, in order to easily feed the paper sheets, the electric stapler is frequently installed in a slant state.
In the staple cartridge, an attachment part for attaching the refill case is formed (refer to Patent Document 2). On a front side of the attachment part, a pressing part is formed being protruded backward, and on a back side of the attachment part, a locking part is formed. When the refill case is attached to the staple cartridge, first, a front lower portion of the refill case is pushed obliquely downward into the staple cartridge so that the front lower portion enters a lower portion of the pressing part of the attachment part. Thereafter, the whole of the refill case is rotated downward around the front lower portion of the refill case, and a back portion of the refill case is locked to the locking part of the attachment part, whereby the refill case is attached to the staple cartridge.    [Patent Document 1] JP-A-7-215565    [Patent Document 2] US2006/0144890
However, according to this attachment mode, when the refill case is rotated downward around the front lower portion of the refill case, a front upper portion of the refill case moves backward and separates from the attachment part of the staple cartridge. Therefore, a clearance gap is produced between the refill case and the staple cartridge.
Therefore, in an electric stapler of a type of driving out a staple from a downside toward an upside, when the electric stapler is operated erroneously in a state where the paper sheets do not exist, an idle-driven staple moves from the staple cartridge along a slant to the clearance gap side between the refill case and the staple cartridge due to vibration of stapling operation. Then, the idle-driven staple further falls from this clearance gap inside the staple cartridge, and enters a feeding path through which the staple led out from the refill case is fed to a drive-out part located at the leading end of the staple cartridge, whereby there is possibility that poor feeding may be caused.